Rooms Disappear, Reappear, Disappear again, and So On...

Same problem here but I'm not using Alexa. Seems to have shown up after recent Windows controller updates. Very annoying!

same problem here. All of a sudden my rooms disappeared and sonos won't let me add the components that were in the missing room. Very annoying indeed!

same issue here

There is generally two issues that cause rooms to disappear from Sonos. One is wifi interference in your local wifi, often not caused by something you've done, but an outside affect. You can read more about that here:

Wifi Interference FAQ

The other issue, which is often exposed when there is a software update, is a duplicate IP address issue in your local wifi. To fix this, first unplug your Sonos devices. Then reboot your router. Once the router is back up, plug in the first Sonos device, if one is wired directly to the router, do that one first, otherwise, whichever one is closest. Give that Sonos device enough time for it to fully boot, then move on to the next Sonos device. Repeat this waiting process for each one, before moving to the next.

That's a temporary fix, of course. It might last years, it might break next software update, it all depends on your router. In order to fix it more permanently, break out your router's manual, and figure out how to assign reserved IP addresses for all of your Sonos equipement....and anything else that's semi-permanently connected to your wifi system.

@ airgetlam.... BS!

My Sonos system works perfectly in all 3 rooms I have a Connect in.
That is, until I have to update a controller. They are connected to my home network via a Sonos Bridge.

I was listening to my Sonos in my office where I am trying to wrap up the aftermath of my workweek.
Then Sonos decides I must update my controller or some features may not function.
So I do the update.
Now I have only one of the 3 connects available.
Guess what, my office isn’t one of them.

Seems Sonos is more concerned about Amazon than they are about their loyal fans.
Which I no longer am.

Sorry about the rant but c’mon, enough with the poorly executed updates already.
You guys used to have the best UI in the business. I’ve help Sonos sell several other systems.
Now I’m thinking of selling mine.

If the update truly was defective, you would see thousands of posts, like the recent Playbar bug that truly was a result of a buggy update. There are not thousands of posts about the recent update. Instead, in 99.99 percent of the cases, "poorly executed updates" are merely updates that uncover an inherent network problem, such as IP conflicts due to a corrupted or recently rebooted router. These are unveiled by the update because a Sonos update requires a rebooting of all Sonos devices, and the mass requesting of new IP addresses by the rebooted devices makes the wonky router, having lost track or it's assignment table, gives out duplicates. Nothing Sonos can do about this, but you can both cure it and prevent it from happening again. Do the following:

Reboot/power cycle your devices in the following order:

Modem
Router
Switches or hubs
Wired Sonos units
Wireless Sonos units
Computers/printers
Wireless devices - phones/tablets etc.

Allow each device to come back up before proceeding to the next. Note that you can permanently prevent duplicate IP addresses by assigning an IP to each device's MAC address in the router setup. See your router manual for details. Do this and you will never experience duplicates again.